Universitas Indonesia, 1995
UI - Skripsi (Membership)
Universitas Indonesia, 1990
UI - Skripsi (Membership)
Situmorang, Thomson, author
Universitas Indonesia, 2002
UI - Skripsi (Membership)
Universitas Indonesia, 2002
UI - Skripsi (Membership)
Damanik, Rachmaihut, author
Universitas Indonesia, 1995
UI - Skripsi (Membership)